Method and mold for forming sheets having reduced surface imperfections
CA 1108819 A · Owner: General Tire & Rubber Company (The) · Inventors: Arnason, Sigurdur I.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure, A mold for compression molding a plastic sheet from a viscous fluid provides more resistance to flow on the side of the sheet designed to be the underside than on the side of the sheet designed to be seen. This resistance to flow can be imparted by roughening the underside of the mold more than the top surface of the mold. The purpose for roughening one surface of the mold more than the other is so that the plastic mass will flow faster on the smoother side of the mold and carry bubbles to the rough side of the mold via a rolling action. By this method employing textured molds the surface, of automotive panels can be made having reduced surface imperfections.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted September 15, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 15, 1998.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.